6 Parameters
6 - 20
E5@C Digital Temperature Controllers User’s Manual (H174)
This parameter is displayed after moving to the Adjustment Level. The four numeric digits to identify the
product code are displayed in the No. 2 display.
When a logic operation is set, a period "." will be displayed on the No. 2. display.
This parameter executes auto-tuning (AT).
l.adj
Adjustment Level Display
• This parameter indicates that the Adjustment Level has been entered.
(The Adjustment Level parameter will not be displayed again even if the M Key is
pressed in the Adjustment Level to scroll through the parameters.)
at
AT Execute/Cancel
The RUN/STOP parameter must be set to RUN
(default: RUN), control must be 2-PID control
(default: ON/OFF), and the Event Input Assignment
parameters must not be set to AT Execute/Cancel.
• The MV is forcibly increased and decreased around the set point to find the
characteristics of the control object. From the results, the PID constants are automatically
set in the Proportional Band (P), Integral Time (I), and Derivative Time (D) parameters.
• Both 100% AT and 40% AT are supported for AT.
Only 100% autotuning is supported for heating and cooling control or for floating
position-proportional control.
• For heating/cooling control, select the tuning methods that is suitable for the cooling
control characteristics in the Heating/Cooling Tuning Method parameter.
• If autotuning is performed with the default settings, the cooling PID constants (i.e.,
Proportional Band (Cooling), Integral Time (Cooling), and Derivative Time (Cooling)
parameters) have the same values as the heating PID constants.
• This parameter will not be displayed when either 100% or 40% AT execute/cancel is set
to be executed using an event input.
• This parameter is normally off. Press the U Key and select at-2 or at-1 to execute
AT. AT cannot be executed when control is stopped or during ON/OFF control.
• The TUNE indicator will light during autotuning.
• When AT execution ends, the parameter setting automatically returns to off.
Related Parameters
RUN/STOP (Operation Level): Page 6-13
Proportional Band, Integral Time, and Derivative Time (Adjustment Level): Page 6-28
Proportional Band (Cooling), Integral Time (Cooling), and Derivative Time (Cooling)
(Adjustment Level): Page 6-29
PID ON/OFF (Initial Setting Level): Page 6-45
Heating/Cooling Tuning Method (Advanced Function Setting Level): Page 6-89
Close/Floating (Initial Setting Level): Page 6-59
Setting range Default
OFF:
AT-2:
AT-1:
AT Cancel
100%AT Execute
40%AT Execute
OFF